1. Field of the Invention
The present invention relates to image forming apparatuses capable of forming images on both sides of a roll sheet.
2. Description of the Related Art
Japanese Patent Laid-Open No. 2008-126530 discloses an image forming apparatus capable of aligning printing positions on front and back sides of a roll sheet with each other in duplex printing. After completion of printing on a front side of a sheet, this image forming apparatus captures an image of the leading end of the sheet to obtain position data of the sheet. From the position data obtained, the image forming apparatus determines a position for printing an image on the back side, and aligns printing positions on the front and back sides of the sheet with each other. Thus, the image forming apparatus can print images at correct positions on the sheet in duplex printing.
As described, Japanese Patent Laid-Open No. 2008-126530 discloses a technique which allows alignment of printing positions on front and back sides of a roll sheet in duplex printing. However, Japanese Patent Laid-Open No. 2008-126530 does not disclose a process of recording-head maintenance necessary for printing on the back side of a sheet. For example, no description is given of a process performed when preliminary ejection needs to be performed at the leading end of a continuous sheet before printing images on the back side, nor of a process performed when a management number needs to be printed.